1. Field of the Invention
The present invention relates to a method of controlling an air-conditioning system for a vehicle. More particularly, the present invention relates to a method of controlling an automotive air-conditioning system which minimizes power consumption of an air-conditioning system by controlling a water pump and a cooling fan in accordance with driving conditions of a vehicle and in accordance with whether an air conditioner operates, and which increases the achievable travel distance by improving the cooling performance and reducing pressure.
2. Description of Related Art
In general, air-conditioning apparatuses include an air-conditioning system for heating/cooling the interior of vehicles.
Those air-conditioning systems, which keep the interior of vehicles at desired temperatures by maintaining the temperature of the interior at appropriate levels regardless of changes in external temperature, heat or cool the interior of vehicles using a refrigerant that is discharged from a compressor and exchange heat through an evaporator while circulating through a condenser, a receiver drier, an expansion valve, the evaporator, and the compressor.
That is, in the air-conditioning systems, a high-temperature and high-pressure refrigerant compressed by the compressor condenses through the condenser and reduces the temperature and humidity of an interior by evaporating through the evaporator after passing through the receiver drier and the expansion valve.
There is a need for developing an environmentally-friendly vehicle that can substantially replace the ICE (Internal Combustion Engine) vehicles, with an increasing concern on energy efficiency and the problem with environmental pollution. These environmentally-friendly vehicles generally include electric vehicles driven by a fuel cell or electricity as the power source, and hybrid vehicles driven by an engine and an electric battery.
In electric vehicles, a cooling system that cools the electric parts is provided as a specific closed circuit, in addition to the air-conditioning system, such that the cooling module that is positioned at the front part of the vehicles and supplies refrigerant or cooling water to the systems is complicated.
Further, when a water-cooled condenser is included in the air-conditioning systems of electric vehicles, the circuit for separately supplying cooling water and a refrigerant is complicated and the maximum load conditions and the operation temperatures of the systems are different, such that when the cooling module is cooled in an air-cooled condenser using a cooling fan and running air, the cooling performance of one of the systems is sufficient but the cooling performance of the other is not sufficient.
That is, since the air-conditioning system is provided as a closed circuit separate from the cooling system in the electric vehicles of the related art, when a water-cooled condenser is used, the layout in the small engine compartment is complicated and the power consumption by the compressor, the cooling fan, and the water pump increases due to the difference in cooling performance according to driving conditions, such that the consumption of electricity increases and the achievable travel distance decreases.
Further, since the maximum load conditions of the cooling system and the air-conditioning system are different, the system is difficult to be controlled in the optimum state, such that the cooling performance of the cooling system and the cooling performance of the air-conditioning system are not at their optimum levels.
Therefore, what is needed is a method of controlling an automotive air-conditioning system which minimizes power consumption by an air-conditioning system and increases the travel distance capability of the vehicle,
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and should not be construed as an acknowledgment or any form of suggestion that this information forms the prior art already known to a person skilled in the art.